This section is intended to introduce various aspects of the art, which may be associated with exemplary embodiments of the present disclosure. This discussion is believed to assist in providing a framework to facilitate a better understanding of particular aspects of the present disclosure. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.
Many oil producing countries are experiencing strong domestic growth in power demand and have an interest in enhanced oil recovery (EOR) to improve oil recovery from their reservoirs. Two common EOR techniques include nitrogen (N2) injection for reservoir pressure maintenance and carbon dioxide (CO2) injection for miscible flooding for EOR. There is also a global concern regarding green house gas (GHG) emissions. This concern combined with the implementation of cap-and-trade policies in many countries makes reducing CO2 emissions a priority for those countries as well as for the companies that operate hydrocarbon production systems therein.
Some approaches to lower CO2 emissions include fuel de-carbonization or post-combustion capture using solvents, such as amines. However, both of these solutions are expensive and reduce power generation efficiency, resulting in lower power production, increased fuel demand and increased cost of electricity to meet domestic power demand. In particular, the presence of oxygen, SOx, and NOx components makes the use of amine solvent absorption very problematic. Another approach is an oxyfuel gas turbine in a combined cycle (e.g., where exhaust heat from the gas turbine Brayton cycle is captured to make steam and produce additional power in a Rankin cycle). However, there are no commercially available gas turbines that can operate in such a cycle and the power required to produce high purity oxygen significantly reduces the overall efficiency of the process.
Moreover, with the growing concern about global climate change and the impact of carbon dioxide emissions, emphasis has been placed on minimizing carbon dioxide emissions from power plants. Gas turbine power plants are efficient and can have a lower cost compared to nuclear or coal power generation technologies. Capturing carbon dioxide from the exhaust of a gas turbine power plant is expensive for the following reasons: (a) the concentration of carbon dioxide in the exhaust stack is low, (b) the volume of gas that needs to be treated is large, (c) the pressure of the exhaust stream is low, and (d) the amount of oxygen present in the exhaust stream is large. All of these factors result in a high cost of carbon dioxide capture.
Accordingly, there is still a substantial need for a low emission, high efficiency power generation and CO2 capture process.